CN116140650B - Metal powder printing device and working method thereof - Google Patents

Abstract

The present invention discloses a metal powder spreading printing device and a working method thereof, wherein the metal powder spreading printing device comprises a frame, a laser, a powder spreading module, and a printing platform, wherein the laser, the powder spreading module, and the printing platform are sequentially installed on the frame from top to bottom, wherein the powder spreading module is used for metal powder to fall from top to bottom to the printing platform and realize the scraping action through a scraper rotating around a central axis; the printing platform is used for carrying a workpiece and synchronously descending vertically and linearly in the process of cooperating with the powder spreading module to realize the powder spreading work of the powder spreading module; the driving mechanism is used for synchronously driving the powder box rotation of the powder spreading module and the vertical linear descent of the printing platform in the printing state. The present invention can realize the simultaneous powder spreading and laser beam, thereby improving the working efficiency of the metal powder spreading 3D printing device.

Description

Metal powder spreading printing equipment and working method thereof

Technical Field

The invention relates to the field of metal powder product processing, in particular to metal powder paving printing equipment.

Background

The working process of the metal powder spreading printing equipment (SLM metal printing equipment) is that a thin layer of metal powder is spread on a platform, and metal particles are melted (or fused) together by using the cross section of a laser scanning assembly, so that the data printing of the layer is completed. After the previous layer is printed, the printing platform is moved down one layer thickness and the doctor blade is moved across the platform to deposit the next layer of powder into the inert printing chamber. And then another layer of metal powder is spread again. This process is repeated layer by layer until printing is complete. Since the doctor blade is translated across the platform, the back and forth translation takes a long time. The chinese patent of application number 201811564012.1 discloses a 3D printing powder spreading system, a 3D printing device and a 3D printing powder spreading method, wherein the 3D printing powder spreading system comprises a disc-shaped powder spreading table, a first cylindrical powder groove wall, a scraper rotating shaft and a plurality of main scrapers, the lower edge of the first cylindrical powder groove wall is connected to the upper surface of the disc-shaped powder spreading table in a sealing manner, a through hole is formed in the center of the disc-shaped powder spreading table, the scraper rotating shaft is arranged in the through hole in a penetrating manner, one ends of the main scrapers are fixedly connected to the scraper rotating shaft, the scraper rotating shaft drives the main scrapers to rotate unidirectionally, the disc-shaped powder spreading table is further provided with at least one powder spreading port, and powder is sent out from the powder spreading port through the unidirectional rotation of the main scrapers. The powder spreading efficiency of the 3D printing powder spreading system is improved, meanwhile, the printing risk is reduced due to unidirectional rotation of the scraper rotating shaft, so that the main scraper can inherit the powder scraped by the previous main scraper to be continuously used for spreading the next layer of powder, continuous powder spreading is realized, and the powder utilization rate is improved. The equipment is characterized in that the equipment comprises a substrate lifting unit, a laser hot melting unit, a main scraper, a laser hot melting unit and a laser projection focal point, wherein the substrate lifting unit drives the substrate to descend by one layer of powder spreading thickness according to a working flow after the layer of powder spreading is completed in the same manner as the traditional powder spreading manner, and the substrate lifting unit carries out the next layer of powder spreading according to the working flow.

Disclosure of Invention

The invention aims to provide metal powder paving printing equipment. The metal powder spreading printing equipment can reduce the connection time of the traditional substrate descending, powder spreading and scraping and laser hot melting processes, and shorten the production period of processing.

The invention solves the problems by adopting the following technical scheme:

A metal powder spreading printing device is characterized by comprising a frame, a laser, a powder spreading module and a printing platform, wherein the laser, the powder spreading module and the printing platform are sequentially arranged on the frame from top to bottom, and the powder spreading module is used for blanking metal powder to the printing platform from top to bottom and realizing a scraping action through a scraper rotating around a central shaft;

the printing platform is used for bearing the workpiece and synchronously carrying out vertical linear descent in the process of matching with the movement of the powder paving module so as to realize the powder paving work of the powder paving module;

And the driving mechanism is used for synchronously carrying out the rotation of the powder box capable of driving the powder spreading module and the vertical linear descending of the printing platform in the printing state.

Further, as an optimization, the powder paving module comprises a bin barrel, a powder box, a scraper and a roller, wherein the bin barrel adopts a structure which is vertically and directly communicated, the powder box is rotationally arranged on the bin barrel, the bin barrel is fixed on a frame, the lower end of the powder box is provided with a strip-shaped powder outlet hole, the roller is rotationally arranged in the powder box, the surface of the roller is provided with a strip-shaped slot, the powder box is fixedly provided with a servo motor for driving the roller to rotate, the axis of the roller is horizontally arranged, the lower edge of the roller extends downwards from the powder outlet hole to be exposed to the lower end of the powder box, the scraper is fixed on the powder box, and in the rotating direction of the powder box, the scraper is positioned behind the roller, the axis of the roller and the edge line of the scraper are arranged in parallel,

Further, as the preference, print platform, including supporting platform and support frame, supporting platform is fixed in on the support frame, and the vertical slidable mounting of support frame is in the frame, and support frame and frame pass through screw-nut mechanism and connect, and the support frame is located the cavity of storehouse section of thick bamboo to realize the relative storehouse section of thick bamboo of support frame and the reciprocates of scraper through screw-nut mechanism.

Further preferably, an annular gap is formed between the supporting platform and the bin barrel.

Further, preferably, the driving mechanism includes a servo driving motor, a screw-nut mechanism, a first gear box, a second gear box and a first electromagnetic clutch, the gear ring is connected with the first gear box, the first gear box is connected to the first electromagnetic clutch, the first electromagnetic clutch is connected with the servo driving motor, the screw-nut mechanism is connected with the second gear box, and the second gear box is connected with the servo driving motor.

Further preferably, the driving mechanism is structured such that a lower vertical transmission shaft is fixed to one end of the first electromagnetic clutch, an upper vertical transmission shaft is fixed to the other end of the first electromagnetic clutch, an upper vertical shaft is fixed to an input shaft of the first gearbox, and an output shaft of the first gearbox drives the gear ring to rotate through a gear. The outer horizontal transmission shaft is connected with the vertical lower vertical transmission shaft through a bevel gear group, synchronous rotation of the outer horizontal transmission shaft and the lower vertical transmission shaft is achieved, the outer horizontal transmission shaft is fixed by a servo driving motor, the outer horizontal transmission shaft is fixed to one end of a second electromagnetic clutch, the inner horizontal transmission shaft is fixed to the other end of the second electromagnetic clutch, the inner horizontal transmission shaft is fixed to an input shaft of a second gearbox, an output shaft of the second gearbox drives a screw rod of a screw rod nut mechanism to rotate, the screw rod of the screw rod nut mechanism is rotatably mounted on a frame, a nut of the screw rod nut mechanism is rotatably mounted on a support frame, and power through the servo driving motor is transmitted to the screw rod sequentially through the outer horizontal transmission shaft, the second electromagnetic clutch, the inner horizontal transmission shaft and the second gearbox, so that the screw rod rotates, and vertical linear movement of the nut of the screw rod nut mechanism is achieved.

Further, as the preference, the supporting platform includes upper base plate, lower retaining member, goes up the retaining member, and the upper base plate is fixed to the top of lower base plate, and the through-hole has been seted up to the central region of upper base plate, and lower locking passes the through-hole of upper base plate, go up the retaining member and screw up on lower retaining member through screw-thread fit, go up the outer wall of retaining member and be provided with the slant compression face that is used for compressing tightly on the slant mesa, and the constant head tank that is used for inserting the locating pin has been seted up to upper base plate upper surface.

Further, as the preference, still include powder recovery module, powder recovery module is including having the recovery storehouse of ring channel, and the recovery ring section of thick bamboo is fixed in the frame, and the ring channel of recovery ring section of thick bamboo is located the below of the clearance between supporting platform and the storehouse section of thick bamboo for the metal powder of scraper outer end is brought into the clearance between supporting platform and the storehouse section of thick bamboo and falls into in the recovery storehouse, and the fixed intercommunication in ring channel bottom has a plurality of outer recovery pipes.

Further, preferably, the lower locking member and the central region of the lower base plate are provided with through holes, and the through holes of the lower base plate are fixed and communicated with the inner recovery pipe.

The working method based on the metal powder spreading printing equipment comprises the following steps:

(1) And a workpiece clamping process, namely, disconnecting the first electromagnetic clutch, connecting the second electromagnetic clutch, and sequentially transmitting power through the servo driving motor to the screw rod through the outer horizontal transmission shaft, the second electromagnetic clutch, the inner horizontal transmission shaft and the second gearbox, so that the screw rod rotates to drive the supporting platform to descend, thereby facilitating clamping of the annular workpiece.

(2) And the tool setting step is to disconnect the first electromagnetic clutch, connect the second electromagnetic clutch, and sequentially transmit the power of the servo driving motor to the screw rod through the outer horizontal transmission shaft, the second electromagnetic clutch, the inner horizontal transmission shaft and the second gearbox, so that the screw rod rotates to drive the supporting platform to ascend, and tool setting action is realized.

(3) And the power of the servo driving motor drives the gear ring to rotate through the outer horizontal transmission shaft, the bevel gear group, the lower vertical transmission shaft, the first electromagnetic clutch, the upper vertical transmission shaft, the first gearbox and the gear, so that the rotation of the scraper is realized, the focal point projected by the laser of the metal powder paving printing equipment also changes along with the rotation direction of the scraper, and in the process, the focal point projected by the laser of the metal powder paving printing equipment also changes along with the rotation direction of the scraper when the scraper of the powder paving module circularly rotates around the central shaft, so that the laser beam can continuously sinter the metal powder in the scraping area along with the movement of the scraper.

(4) And a workpiece taking procedure, namely, switching off the first electromagnetic clutch, switching on the second electromagnetic clutch, and sequentially transmitting power through the outer horizontal transmission shaft, the second electromagnetic clutch, the inner horizontal transmission shaft and the second gearbox to the screw rod by virtue of power of the servo driving motor, so that the screw rod rotates to drive the supporting platform to descend, and the workpiece is conveniently taken down.

(5) And the metal powder recovery procedure comprises the steps of after the workpiece is taken down, switching on the first electromagnetic clutch, switching on the second electromagnetic clutch, sequentially transmitting power through the servo driving motor to the screw rod through the outer horizontal transmission shaft, the second electromagnetic clutch, the inner horizontal transmission shaft and the second gearbox, so that the screw rod rotates to drive the supporting platform to rise, and simultaneously, sequentially transmitting power through the outer horizontal transmission shaft, the bevel gear group, the lower vertical transmission shaft, the first electromagnetic clutch, the upper vertical transmission shaft, the first gearbox and the gear to drive the gear ring to rotate, thereby realizing the reverse rotation of the scraper, pushing the metal powder into a gap between the supporting platform and the bin barrel by the scraper and falling into the recovery bin, and pushing the metal powder into the through holes of the center areas of the lower locking piece and the lower substrate by the scraper to enter the inner recovery pipe, so as to realize the automatic recovery of the metal powder.

Compared with the prior art, the metal powder spreading grafting printing equipment synchronously drives the powder spreading module and the printing platform, has simple control logic and higher synchronism of the powder spreading module and the printing platform, is favorable for realizing the improvement of control precision, can realize the rotation of powder spreading and scraping and the synchronous descending of the supporting platform, and controls the laser to melt the metal alloy powder along the rotation direction of powder spreading and scraping and stacks the metal alloy powder into compact workpieces. Because the existing powder paving mechanism sequentially works due to powder paving and laser beams in the layer-by-layer superposition cyclic manufacturing process, a great amount of time is consumed. The invention can realize simultaneous powder spreading and laser beam by adopting the driving mechanism, thereby improving the working efficiency of the metal powder spreading 3D printing equipment.

Drawings

Fig. 1 is a schematic diagram of a metal powder spreading 3D printing apparatus according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of an internal structure of a metal powder spreading 3D printing apparatus according to an embodiment of the present invention.

Fig. 3 is a schematic structural view of a powder spreading module according to an embodiment of the present invention.

Fig. 4 is a schematic view of a mounting structure of a doctor blade according to an embodiment of the invention.

Fig. 5 is a schematic view of the structure of the recycling bin according to the embodiment of the present invention.

Fig. 6 is an enlarged schematic view of the structure at a in fig. 2 according to an embodiment of the present invention.

Fig. 7 is an enlarged schematic view of the structure at B in fig. 2 according to the embodiment of the present invention.

Fig. 8 is a schematic diagram of the position change of the doctor blade during printing according to an embodiment of the invention.

Reference numerals of molding bin 1, frame 2, laser 3, bin cylinder 41, powder box 42, doctor blade 43, roller 44, slot 45, gear ring 46, gap 47, support platform 51, support frame 52, upper base plate 54, lower base plate 55, lower locking member 56, upper locking member 57, diagonal pressing surface 58, positioning groove 59, servo drive motor 61, lower vertical drive shaft 62, first electromagnetic clutch 63, upper vertical drive shaft 64, first gearbox 65, bevel gear set 66, outer horizontal drive shaft 67, second electromagnetic clutch 68, inner horizontal drive shaft 69, second gearbox 610, screw rod 611, recovery bin 71, annular groove 72, outer recovery tube 73, inner recovery tube 74, bellows sleeve 75, through holes 81, 83, 93, annular workpiece 9, positioning pin 91, diagonal table 92

Detailed Description

The present invention will be described in further detail by way of examples with reference to the accompanying drawings, which are illustrative of the present invention and not limited to the following examples.

Referring to fig. 1-8, the metal powder spreading 3D printing equipment of the embodiment comprises a molding bin 1, a frame 2, a laser 3, a powder spreading module and a printing platform, wherein the laser 3, the powder spreading module and the printing platform are sequentially arranged on the frame 2 from top to bottom.

The powder spreading module comprises a bin barrel 41, a powder box 42, a scraper 43 and a roller 44, wherein the bin barrel 41 adopts an up-down straight-through structure, the powder box 42 is rotatably arranged on the bin barrel 41, the bin barrel 41 is fixed on a frame 2, the lower end of the powder box 42 is provided with a strip-shaped powder outlet hole, the roller 44 is rotatably arranged in the powder box 42, the surface of the roller 44 is provided with a strip-shaped groove 45, a servo motor for driving the roller 44 to rotate is fixed on the powder box 42, the axis of the roller 44 is horizontally arranged, the lower edge of the roller 44 extends downwards from the powder outlet hole to be exposed to the lower end of the powder box 42, the scraper 43 is fixed on the powder box 42, and in the rotation direction of the powder box 42, the scraper 43 is positioned behind the roller 44, the axis of the roller 44 and the blade line of the scraper 43 are arranged in parallel,

Preferably, in this embodiment, as shown in fig. 5, the cartridge 41 is coaxially rotatably mounted with a gear ring 46 (the axis of the gear ring 46 is a central axis), and the powder box 42 is fixed to the gear ring 46, so that the powder box 42 has a degree of freedom with respect to the cartridge 41,

The printing platform comprises a supporting platform 51 and a supporting frame 52, wherein the supporting platform 51 is fixed on the supporting frame 52, the supporting frame 52 is vertically and slidably arranged on the frame 2, the supporting frame 52 is connected with the frame 2 through a screw-nut mechanism, the supporting frame 52 is positioned in a hollow cavity of the bin 41, and the supporting frame 52 moves up and down relative to the bin 41 and the scraper 43 through the screw-nut mechanism.

Preferably, in this embodiment, there is an annular gap 47 (see fig. 3) between the support platform 51 and the cartridge 41.

The driving mechanism comprises a servo driving motor 61, a screw nut mechanism, a first gear box 65, a second gear box 610 and a first electromagnetic clutch 63, wherein the gear ring 46 is connected with the first gear box 65, the first gear box 65 is connected to the first electromagnetic clutch 63, the first electromagnetic clutch 63 is connected with the servo driving motor 61, the screw nut mechanism is connected with the second gear box 610, and the second gear box 610 is connected with the servo driving motor 61.

By adopting the driving mode, the gear ring 46 can be driven to rotate through the first gearbox 65 by the servo driving motor 61, so that the powder box 42, the scraper 43 and the roller 44 can rotate relative to the center of the bin 41, the servo driving motor 61 drives the screw-nut mechanism to start working through the second gearbox 610, and the support frame 52 can move up and down relative to the scraper 43, and the servo driving motor 61 can synchronously drive the powder spreading module and the printing platform, so that the control logic is simple, the synchronism of the powder spreading module and the printing platform is higher, the control precision is improved, the rotation of powder spreading and leveling and the synchronous descending of the support platform 51 can be realized, the laser 3 controls the laser beam to melt metal alloy powder along the rotation direction of powder spreading and leveling, and the laser beam is stacked into the upper half part of a compact workpiece. Because the existing powder paving mechanism sequentially works due to powder paving and laser beams in the layer-by-layer superposition cyclic manufacturing process, a great amount of time is consumed. The invention can realize simultaneous powder spreading and laser beam by adopting the driving mechanism, thereby greatly improving the working efficiency of the metal powder spreading 3D printing equipment.

However, it should be noted that, since the existing SLM technology generally performs slicing operation on a three-dimensional model and adds supporting and layering processing to obtain cross-section profile data of the three-dimensional model, and performs scanning path processing on the profile data by using path planning software, the data after path planning is led into the SLM device, while in the working process of the metal powder spreading 3D printing device of the present invention, the laser beam works around the center of the bin 41 after the doctor blade 43, the focal point of the laser beam is not in a uniform plane, there is a fall of 0.01mm-0.05mm or more (depending on the manufacturing precision of the device) between the lowest point and the highest point, there is a certain negative influence on the progress of 3D printing, but it improves the processing efficiency of the device, and the dimensional precision can be corrected by subsequent machining, and for workpieces whose processing precision requirements are not particularly high (the processing tolerance allows 0.05mm or more than 0.1 mm), the metal powder spreading 3D printing device of the present invention has obvious advantages from the aspect of processing efficiency.

Since the doctor 43 of the metal powder spreading 3D printing apparatus is rotationally scraped, there is little accumulation of metal powder in the area of the rotational center point, and thus the metal powder spreading 3D printing apparatus is suitable for 3D printing of some workpieces (e.g., annular workpieces) having a center hole, which avoids the metal powder in the area of the rotational center point, and for non-annular workpieces, it is necessary to arrange the metal powder in an area away from the center axis for printing.

Preferably, in the present embodiment, as shown in fig. 2, a lower vertical transmission shaft 62 is fixed to one end of a first electromagnetic clutch 63, an upper vertical transmission shaft 64 is fixed to the other end of the first electromagnetic clutch 63, an upper vertical shaft fixes an input shaft of a first gearbox 65, and an output shaft of the first gearbox 65 drives a ring gear 46 to rotate through a gear. The outer horizontal transmission shaft 67 is connected with the vertical transmission shaft through the bevel gear group 66, synchronous rotation of the outer horizontal transmission shaft 67 and the lower vertical transmission shaft 62 is achieved, the servo driving motor 61 fixes the outer horizontal transmission shaft 67, the outer horizontal transmission shaft 67 is fixed to one end of the second electromagnetic clutch 68, the other end of the second electromagnetic clutch 68 is fixed to the inner horizontal transmission shaft 69, the inner horizontal transmission shaft 69 is fixed to an input shaft of the second gearbox 610, an output shaft of the second gearbox 610 drives a screw rod 611 of a screw-nut mechanism to rotate, the screw rod 611 of the screw-nut mechanism is rotatably mounted on the frame 2, nuts of the screw-nut mechanism are rotatably mounted on the support frame 52, and power of the servo driving motor 61 is transmitted to the screw rod 611 sequentially through the outer horizontal transmission shaft 67, the second electromagnetic clutch 68, the inner horizontal transmission shaft 69 and the second gearbox 610, so that the screw rod 611 rotates, and vertical linear movement of nuts of the screw-nut mechanism is achieved.

With the above-described drive mechanism, the following process steps can be achieved by providing two electromagnetic clutches (first electromagnetic clutch 63, second electromagnetic clutch 68):

(1) When clamping a workpiece, the first electromagnetic clutch 63 is disconnected, the second electromagnetic clutch 68 is connected, and the power of the servo driving motor 61 is sequentially transmitted to the screw rod 611 through the outer horizontal transmission shaft 67, the second electromagnetic clutch 68, the inner horizontal transmission shaft 69 and the second gearbox 610, so that the screw rod 611 rotates to drive the supporting platform 51 to descend, and the workpiece is conveniently clamped.

(2) When in tool setting, the first electromagnetic clutch 63 is disconnected, the second electromagnetic clutch 68 is connected, and the power of the servo driving motor 61 is sequentially transmitted to the screw rod 611 through the outer horizontal transmission shaft 67, the second electromagnetic clutch 68, the inner horizontal transmission shaft 69 and the second gearbox 610, so that the screw rod 611 rotates to drive the supporting platform 51 to ascend, and tool setting action is realized.

(3) When the powder is spread and printed, the first electromagnetic clutch 63 is connected, the second electromagnetic clutch 68 is connected, the power of the servo driving motor 61 is sequentially transmitted to the screw rod 611 through the outer horizontal transmission shaft 67, the second electromagnetic clutch 68, the inner horizontal transmission shaft 69 and the second gearbox 610, so that the screw rod 611 rotates to drive the supporting platform 51 to descend, and meanwhile, the power of the servo driving motor 61 sequentially drives the gear ring 46 to rotate through the outer horizontal transmission shaft 67, the bevel gear group 66, the lower vertical transmission shaft 62, the first electromagnetic clutch 63, the upper vertical transmission shaft 64, the first gearbox 65 and the gear, so that the rotation of the scraper 43 is realized. As shown in fig. 8, when the doctor blade 43 is at the position P1, the focal projection area of the laser 3 is located at P3, and when the doctor blade 43 is rotated to P2 in the direction shown in the figure, the focal projection area of the laser 3 is also transferred to P3, and the laser is sequentially circulated, thereby realizing continuous printing operation. In the process, the doctor blade 43 of the powder spreading module circularly rotates around the central shaft, and simultaneously, the focal point projected on the surface of the metal powder by the laser 3 of the metal powder spreading printing device also realizes the change of a focal point projection area along with the rotation direction of the doctor blade 43, so that the laser beam can continuously sinter the metal powder in the scraping area of the doctor blade 43 along with the movement of the doctor blade 43. During this process, the support platform 51 carrying the workpiece is moved synchronously downwards. According to the method, powder spreading and laser beam simultaneous operation are performed, so that the working efficiency of metal powder printing of the metal powder spreading 3D printing equipment is greatly improved, and the focus projection area of the laser 3 moves along with the rotation of the rotary scraper 43, so that the main scraper 43 does not occupy the section outline area of hot melting required by the focus of the laser 3 in the laser hot melting process.

(4) When the printing and workpiece taking are finished, the first electromagnetic clutch 63 is disconnected, the second electromagnetic clutch 68 is connected, and the power of the servo driving motor 61 is sequentially transmitted to the screw rod 611 through the outer horizontal transmission shaft 67, the second electromagnetic clutch 68, the inner horizontal transmission shaft 69 and the second gearbox 610, so that the screw rod 611 rotates to drive the supporting platform 51 to descend, and the workpiece is conveniently taken down.

Further, in this embodiment, in order to facilitate graft printing on some annular workpieces 9 with larger sizes (for example, the ring of the granulating template), and in the case that the hole diameters of the upper and lower sections of such annular workpieces 9 are consistent, in order to improve the convenience of clamping the annular workpieces 9 on the base portion before graft printing, as shown in fig. 6, in the machining process of the annular workpieces 9 on the base portion, a positioning pin 91 with a truncated cone shape and located on the bottom surface of the annular workpiece 9 and an inclined table 92 located on the inner wall of the through hole 93 of the annular workpiece 9 may be machined. The supporting platform 51 comprises an upper base plate 54, a lower base plate 55, a lower locking member 56 and an upper locking member 57, wherein the upper base plate 54 is fixed above the lower base plate 55, a through hole 83 is formed in the central area of the upper base plate 54, the lower locking member passes through the through hole 83 of the upper base plate 54, the upper locking member 57 is screwed on the lower locking member 56 through threaded fit, an inclined pressing surface 58 for pressing on an inclined table top 92 is arranged on the outer wall of the upper locking member 57, and a positioning groove 59 for inserting a positioning pin 91 is formed in the upper surface of the upper base plate 54. The locating pins 91 and the angled table 92 need to be removed by a CNC machine after a subsequent machining step.

In the process of clamping the annular workpiece 9, the annular workpiece 9 is placed on the upper substrate 54, the positioning pins 91 of the annular workpiece 9 are inserted into the positioning grooves 59 to position the annular workpiece 9, then the upper locking piece 57 is screwed on the lower locking piece 56 through threaded fit, and the inclined pressing surface 58 of the upper locking piece 57 is pressed on the inclined table surface 92 of the annular workpiece 9, so that the positioning and clamping of the annular workpiece 9 are completed. When the upper retaining member 57 is removed, the upper retaining member 57 can be removed from the upper end of the workpiece (the upper retaining member 57 should be smaller in size than the central aperture of the annular workpiece).

Further, in order to solve the problem of metal powder recovery of the metal powder spreading 3D printing equipment, in this embodiment, the metal powder spreading 3D printing equipment further comprises a powder recovery module, the powder recovery module comprises a recovery bin 71 with an annular groove 72, the recovery annular cylinder is fixed on the frame 2, the annular groove 72 of the recovery annular cylinder is located below the gap 47 between the supporting platform 51 and the bin cylinder 41, so that the metal powder at the outer end of the scraper 43 is brought into the gap 47 between the supporting platform 51 and the bin cylinder 41 and falls into the recovery bin 71, and a plurality of outer recovery pipes 73 are fixedly communicated with the bottom of the annular groove 72.

The through holes 81 and 82 are respectively formed in the center areas of the lower locking piece 56 and the lower substrate 55, the through holes 82 of the lower substrate 55 are fixed and communicated to the inner recovery pipe 74, and the outer recovery pipe 73 and the inner recovery pipe 74 are communicated to a metal powder filtering recovery system through negative pressure vacuumizing equipment and used for continuously recycling metal powder after filtering. In order to avoid escape of the metal powder in the recovery bin 71, a bellows sleeve 75 is provided on the outer wall of the recovery bin 71, the lower end of the bellows sleeve 75 is fixed to the outer wall of the recovery bin 71, and the upper end of the bellows sleeve 75 is fixed to the lower surface of the upper top plate of the frame 2.

With the above-described driving mechanism, the following process steps can be achieved by providing two electromagnetic clutches (first electromagnetic clutch 63, second electromagnetic clutch 68):

the metal powder is recovered, after the workpiece is removed, the first electromagnetic clutch 63 is connected, the second electromagnetic clutch 68 is connected, the power of the servo driving motor 61 is sequentially transmitted to the screw rod 611 through the outer horizontal transmission shaft 67, the second electromagnetic clutch 68, the inner horizontal transmission shaft 69 and the second gearbox 610, so that the screw rod 611 rotates to drive the supporting platform 51 to ascend, and simultaneously, the power of the servo driving motor 61 sequentially drives the gear ring 46 to rotate through the outer horizontal transmission shaft 67, the bevel gear group 66, the lower vertical transmission shaft 62, the first electromagnetic clutch 63, the upper vertical transmission shaft 64, the first gearbox 65 and the gear, so that the reverse (relative to the powder spreading printing) rotation of the scraper 43 is realized, the metal powder is pushed into a gap 47 between the supporting platform 51 and the bin 41 by the scraper 43 and falls into the recovery bin 71, and is pushed into the lower locking piece 56 and the through hole 82 in the central area of the lower base plate 55 by the scraper 43 to enter the inner recovery tube 74 (before the operation, the workpiece needs to be removed), and automatic recovery of the metal powder is realized.

The foregoing description of the invention is merely exemplary of the invention. Those skilled in the art may make various modifications or additions to the described embodiments or substitutions, without departing from the scope of the invention as defined in the accompanying claims.

Claims (8)

1. The utility model provides a metal shop powder lithography apparatus, includes frame, laser instrument, shop's powder module, print platform top-down install in proper order in the frame, its characterized in that:

The powder spreading module is used for blanking metal powder from top to bottom to the printing platform and realizing the scraping action through a scraper rotating around a central shaft;

the printing platform is used for bearing the workpiece and synchronously carrying out vertical linear descent in the process of matching with the movement of the powder paving module so as to realize the powder paving work of the powder paving module;

the driving mechanism is used for synchronously driving the powder box of the powder spreading module to rotate and the vertical straight line of the printing platform to descend in a printing state;

The powder paving module comprises a bin barrel, a powder box, a scraper and a roller, wherein the bin barrel is of an up-down straight-through structure, the powder box is rotatably installed on the bin barrel, the bin barrel is fixed on a frame, a strip-shaped powder outlet hole is formed in the lower end of the powder box, the roller is rotatably installed in the powder box, a strip-shaped slot is formed in the surface of the roller, a servo motor for driving the roller to rotate is fixed on the powder box, the axis of the roller is horizontally arranged, the lower edge of the roller extends downwards from the powder outlet hole to be exposed to the lower end of the powder box, the scraper is fixed on the powder box, and in the rotating direction of the powder box, the scraper is positioned behind the roller, and the axis of the roller and the cutting edge line of the scraper are arranged in parallel;

The driving mechanism is structurally characterized in that a lower vertical transmission shaft is fixed to one end of a first electromagnetic clutch, an upper vertical transmission shaft is fixed to the other end of the first electromagnetic clutch, an upper vertical transmission shaft is fixed to an input shaft of a first gearbox, an output shaft of the first gearbox drives a gear ring to rotate through a gear, an outer horizontal transmission shaft is connected with the vertical lower vertical transmission shaft through a bevel gear set to realize synchronous rotation of the outer horizontal transmission shaft and the lower vertical transmission shaft, a servo driving motor is fixed to the outer horizontal transmission shaft, the outer horizontal transmission shaft is fixed to one end of a second electromagnetic clutch, an inner horizontal transmission shaft is fixed to the other end of the second electromagnetic clutch, an input shaft of the second gearbox is fixed to the inner horizontal transmission shaft, an output shaft of the second gearbox drives a screw rod of a screw rod nut mechanism to rotate, the screw rod of the screw rod nut mechanism is rotatably mounted on a frame, and the screw rod of the screw rod nut mechanism is sequentially driven to the screw rod through the outer horizontal transmission shaft, the second electromagnetic clutch, the inner horizontal transmission shaft and the second gearbox, so that the screw rod is enabled to rotate, and the screw rod nut of the screw rod mechanism is enabled to vertically and linearly move.

2. The metal powder spreading printing equipment according to claim 1, wherein the printing platform comprises a supporting platform and a supporting frame, the supporting platform is fixed on the supporting frame, the supporting frame is vertically and slidably arranged on the frame, the supporting frame is connected with the frame through a screw-nut mechanism, the supporting frame is positioned in a hollow cavity of the bin barrel, and the supporting frame moves up and down relative to the bin barrel and the scraper through the screw-nut mechanism.

3. The metal powder spreading printing equipment as set forth in claim 2, wherein an annular gap is provided between the support platform and the cartridge.

4. The metal powder spreading printing apparatus as set forth in claim 1, wherein the drive mechanism comprises a servo drive motor, a screw-nut mechanism, a first gearbox, a second gearbox, and a first electromagnetic clutch, the ring gear is connected to the first gearbox, the first gearbox is connected to the first electromagnetic clutch, the first electromagnetic clutch is connected to the servo drive motor, the screw-nut mechanism is connected to the second gearbox, and the second gearbox is connected to the servo drive motor.

5. The metal powder spreading printing equipment according to claim 2, wherein the supporting platform comprises an upper substrate, a lower locking piece and an upper locking piece, the upper substrate is fixed above the lower substrate, a through hole is formed in the central area of the upper substrate, the lower locking piece penetrates through the through hole of the upper substrate, the upper locking piece is screwed on the lower locking piece through threaded fit, an inclined pressing surface used for pressing on an inclined table top is arranged on the outer wall of the upper locking piece, and a positioning groove used for inserting a positioning pin is formed in the upper surface of the upper substrate.

6. The metal powder spreading printing equipment according to claim 1, further comprising a powder recovery module, wherein the powder recovery module comprises a recovery bin with an annular groove, the recovery annular cylinder is fixed on the frame, the annular groove of the recovery annular cylinder is positioned below a gap between the supporting platform and the bin cylinder, so that metal powder at the outer end of the scraper is brought into the gap between the supporting platform and the bin cylinder and falls into the recovery bin, and a plurality of outer recovery pipes are fixedly communicated with the bottom of the annular groove.

7. The metal powder spreading printing equipment according to claim 5, wherein the lower locking piece and the central area of the lower base plate are provided with through holes, and the through holes of the lower base plate are fixed and communicated with the inner recovery pipe.

8. A method of operating a metal dusting printing apparatus according to any of claims 1 to 7 comprising the steps of:

(1) The work piece clamping process comprises the steps of disconnecting the first electromagnetic clutch, connecting the second electromagnetic clutch, and sequentially transmitting power of the servo driving motor to the screw rod through the outer horizontal transmission shaft, the second electromagnetic clutch, the inner horizontal transmission shaft and the second gearbox, so that the screw rod rotates to drive the supporting platform to descend, and the work piece is conveniently clamped;

(2) The tool setting step comprises the steps of disconnecting the first electromagnetic clutch, connecting the second electromagnetic clutch, and sequentially transmitting power of the servo driving motor to the screw rod through the outer horizontal transmission shaft, the second electromagnetic clutch, the inner horizontal transmission shaft and the second gearbox, so that the screw rod rotates to drive the supporting platform to ascend, and the upper surface of a workpiece is adjusted to be flush with the lower edge of the scraper, so that tool setting action is realized;

(3) The method comprises the steps of connecting a first electromagnetic clutch, connecting a second electromagnetic clutch, sequentially transmitting power of a servo driving motor to a screw rod through an outer horizontal transmission shaft, the second electromagnetic clutch, an inner horizontal transmission shaft and a second gearbox, so that the screw rod rotates to drive a supporting platform to descend, and simultaneously, driving a gear ring to rotate through the power of the servo driving motor, an outer horizontal transmission shaft, a bevel gear group, a lower vertical transmission shaft, the first electromagnetic clutch, an upper vertical transmission shaft, the first gearbox and a gear, so that rotation of a scraper is realized, and simultaneously, a focal point projected by a laser of a metal powder paving printing device also realizes focal point area change along with the rotation direction of the scraper;

(4) A work piece taking procedure, namely, a first electromagnetic clutch is disconnected, a second electromagnetic clutch is connected, and the power of a servo driving motor is sequentially transmitted to a screw rod through an outer horizontal transmission shaft, the second electromagnetic clutch, an inner horizontal transmission shaft and a second gearbox, so that the screw rod rotates to drive a supporting platform to descend, and the work piece is conveniently taken down;

(5) And the metal powder recovery procedure comprises the steps of after the workpiece is taken down, switching on the first electromagnetic clutch, switching on the second electromagnetic clutch, sequentially transmitting power through the servo driving motor to the screw rod through the outer horizontal transmission shaft, the second electromagnetic clutch, the inner horizontal transmission shaft and the second gearbox, so that the screw rod rotates to drive the supporting platform to rise, and simultaneously, sequentially transmitting power through the outer horizontal transmission shaft, the bevel gear group, the lower vertical transmission shaft, the first electromagnetic clutch, the upper vertical transmission shaft, the first gearbox and the gear to drive the gear ring to rotate, thereby realizing the reverse rotation of the scraper, pushing the metal powder into a gap between the supporting platform and the bin barrel by the scraper and falling into the recovery bin, and pushing the metal powder into the through holes of the center areas of the lower locking piece and the lower substrate by the scraper to enter the inner recovery pipe, so as to realize the automatic recovery of the metal powder.